3.2 Volcanic Activity



Vocabulary



magma chamber-a place where magma collects into a pocket
pipe-a long tube where magma flows to the surface from the magma chamber
vent-a place on the volcano where magma pours out of
lava flow-a area covered by lava as it pours out of the vent
crater-a bowl shaped area that may form at the top of the volcano at the top of the central vent
Silica-made from the element silicon and oxygen
pahoehoe-a hot, fast moving lava
aa-a cooler, slow moving lava
pyroclastic flow-occurs when explosive eruption trows ash, cinders, bombs, and maybe even gases
active-a live volcano is erupting and may erupt in the future
dormant-a sleeping volcano that is "sleeping" and may erupt in the future
extinct-a volcano that is no longer active
hot spring-a area where groundwater as been heated and rises to the surface forming a natural pool
geyser-a fountian of water that erupts from the ground
geothermal energy-how energy can be made using magma heated water from hot springs

Outline



Volcanic activity

  • How magma reaches the surface
    • Magma rises
      • magma is less dense that rock so it moves up
    • A volcano erupts
      • During an eruption, the dissolved gases rush out carrying magma with them
  • Inside a volcano
    • a volcano always has a pocket beneath them filled with molten material
  • Characteristics of magma
  • Types of volcanic eruptions
    • quiet eruptions
      • a volcano erupts smoothly during quiet eruptions
      • there two types of magma that produce quiet eruptions
    • Explosive eruptions
      • explosive eruptions erupts wildly with bottled up gas and huge rocks
  • Stages of a volcano
    • active
      • active volcanos are volcanos that continue to erupt
    • dormant
      • dormant volcanos are volcano that are "sleeping" which mean that they havent erupt in a long time
    • extinct
      • extinct volcanos no longer erupt
  • Other types of volcanic activity
      • volcanos might make other things that dont involve lava
        • one example is geysers and hot springs
  • Monitoring volcanoes
      • You can predict the time of an eruption
  • Volcano hazards
      • not all infomation on volcanos are acurate